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codex-rs/core/src/agent/control.rs

@@ -133,6 +133,8 @@ fn keep_forked_rollout_item(item: &RolloutItem) -> bool {
 /// which keeps the registry scoped to that root thread rather than the entire `ThreadManager`.
 #[derive(Clone, Default)]
 pub(crate) struct AgentControl {
+    /// ID shared by the whole agent control session. This means every sub-agents from a common
+    /// root share the same session ID.
     session_id: SessionId,
     /// Weak handle back to the global thread registry/state.
     /// This is `Weak` to avoid reference cycles and shadow persistence of the form